Amoxicillin is a semi-synthetic, orally absorbed, broad-spectrum antibiotic. Chemically, it is (2S,5R,6R)-6-[(R)-(−)-2-amino-2-(p-hydroxyphenyl)acetamido]-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid trihydrate. Amoxicillin is widely used in the standard eradication treatment of gastric and duodenal ulcers, which are associated with Helicobacter pylori infection, combined with a second antibiotic and an acid-suppressing agent. H. pylori, a prevalent human-specific pathogen, is a causative agent in chronic active gastritis, gastric and duodenal ulcers, and gastric adenocarcinoma. Treatment of H. pylori remains a challenging proposition. One reason for incomplete eradication of H. pylori may be the short residence time of the dosage form in the stomach so that effective antimicrobial concentration cannot be achieved in the gastric mucous layer or epithelial cell surfaces where H. pylori exists. Another reason may be the degradation of amoxicillin in gastric acid. A number of researchers have prepared and reported new amoxicillin formulations such as float tablets, mucoadhesive tablets, and formulations with pH-sensitive excipients, which are able to reside in the gastrointestinal tract for a longer extended period of time for more effective H. pylori eradication.
There is a need for an amoxicillin composition for delivering amoxicillin in the stomach, which would provide a long resident time and sustained action, and increase the efficiency of the drug.